1. Field of the Invention
The present invention relates to a rotation angle detection device and a throttle valve control device using the same. More particularly, the present invention relates to a throttle valve rotation angle detection device of an internal combustion engine, and a throttle valve control device using the same.
2. Description of Related Art
A throttle position sensor (a throttle valve rotation angle detection device) of an internal combustion engine is taught, for example, by Japanese Laid-Open Patent Publication No. 2007-92608.
The throttle position sensor includes a sensor circuitry (a magneto-electric transducer) that is constructed of a sensor (a magnetism detection portion) and a signal processing IC (an operation voltage output portion) that are disposed in an L-shape. The sensor circuitry is molded by insert molding of resin to form a magnetic field detector assembly. The magnetic field detector assembly is integrally provided with a cover (a fixture member) by insert molding of resin.
In the conventional throttle position sensor thus constructed, two separate insert molding processes (an insert molding process for forming the magnetic field detector assembly and an additional insert molding process for proving the cover to the magnetic field detector assembly) must be performed. This may lead to increased manufacturing steps and increased manufacturing costs. In addition, a molding pressure and a molding heat can be applied to the sensor circuitry during the insert molding processes. The molding pressure and the molding heat may lead to decreased detection performance or failure of the sensor circuitry.